Black-out system



" Nov. 16, 1943.

P. HINSHELWOOD BLACK-OUT SYSTEM Filed Jan. 30, 1942 3 Sheets-Sheet 2 Nov. 16,1943. P, i-IINSHELWOOD 2,334,194

BLACK-OUT SYSTEM INVENT OR.

HIS ATTORNEY PeterHinsheZwaad v Patented Nov. 16, 1943 i 3 UN E TA ES PATENT O FFlCE'j] I t c 2,334,194.51 v

' BLACK-OUT system, qfreter fiinshelwood j qlii cagoflll. Application January 30, 1942, SerialNo. 428,921

' 16 Claims:

My invention relatesto a novel electrical system or circuit and the object thereof is to proteins-2) 1 f vide novel means for operating or controlling an electrical circuit and equipmenn machinery or other load therein by the operation of another circuit, such as a telephone-or like communicationsystem or circuit, and especially thec'all or signal circuit thereof, Without electrical connection or interference with 'thelattercircuit, but only, solely and purely by mechanical operation, intervention or interposition of a controlling means for the-first circuit from the signal circuit thereof without requiring aresponse or answering of the signal or call suchas bylifting the receiver, of a telephone or responding orally thereto andflwithout drawing 'on the currentor electrical circuit connecting withthe second circuit such as a telephone or like call or comm'unif cation circuit or-system. r t a 1 Another object; of [the invention is to provide a black-out system or control fora'lightingcir suit to turn the same on or off' at any desired time, or whenever the emergencyshould arise or,

be terminated, merely by calling a telephone number or substation, preferablykhow'n only to those in authorityfor such purposes or emergene cies and merely by the usepf switches in connection with the controlled circuit or circuits operated mechanically by callingsaid numbers, pref-i erably two, one for opening the" circuit, and the other for closing the circuitso controlled 'for causing a black-out or turning off the lights and then turning on the lights,'respectively- A,further object or the invention is to provide 1 means for controlling an electrical' circuit and its equipment, such as a lighting circuit'by means of tongue to-operate aswitch controlling the operationof said-lighting or other separate circuit in which it; is included. l

Another object of the invention-is to provide a system of electric circuit control whereby upon calling orsignaling a certain number or subscriber known only to a, proper authority, the movement of 't-he signal bell clapperthereof may be used to mechanically close a normally open switch positioned adjacent or in juxtaposition thereto for directly or indirectly-completing or closing an -electrical circuit "for a'lighting system or havingother current consuming devices; or for directly completing a circuitior-thelighting system o'f' a building or area, machinery or other lo'ad therintand by calling another'number or subscriber, will similarlyoperate another but normally closed switch'to open the circuitthereof fol-directly or indirectly-opening the circuit of said light'ing system or included current consum ing'devices' machineryor load therein, so that the system is adapted, among other purposes and uses, for blackouts of difle'rent areasand buildings and'for'relighting'or re-es'tablishin'g the controlled circuit or circuits, asdesired, such as after a predetermined perioclor when the danger is passed. l f

Another objectoff the invention is' to provide a holdin'g means for holding the circuit closed when certain telephone number is called or signailed to close a'switchco'ntrolling a lighting or other-==circuit,'*so that said circuit will remain another or controlled circuit, such as a telephone circuit, whereby the first circuit maybe rendered operative orinoperative, as desired, over a pre scribed-or'predetermined section, area, building, home and equipmenttherein, or independently of the telephonecircuit by other operating means;

Another objector the invention is, to provide an electrical control system or circuit whereby a communicating system, such'fas jatelephone circuit, may be used to mechanically operate a switch at a substation upon callingsaid substa tion, subscriber or a certain and preferably secret telephone number known onlytothose having charge thereof, so that upon the operation of the signal circuit, or call bell thereof, a switch or controlling means for a'lighting or other sep- 'arate circuit will be mechanically operated such 1 as by movement of thesignah buz zer or call bell V hammer, striker, clapper or metal "bell ringer closed "when completed} foras long a period as desired, or, until"another 'telephone number is called to operate for open-another controlling;

switch to open said "circuit and extinguish the lights or render the load therein inoperative, or to release a switch,-gravity or otherwise operated, to" normally 'and"automatically open a circuit controlling'said lighting system or load.

A still further obdectof the invention is to employ the striking power or physical movement of the hammer or metal tongue of the bell ringer of asig'nalj of atelephone set, the result of the magnetization of the solenoids of the signal-circui't' thereof to close a normally open momentary contact switch'to close a magnetic circuit which closes the main 'switch or contactor of a consuming circuit or controlling switch thereof to allow current to flow-to a motor for operating a large or giant oil switch controlling a lighting circuit or 'other'energy consuming devices,-'-' o the-other hand, when itis desired to open the circuit and stop thernotor or current from flowing to any of thecurrent-consuming devices or operation of the circuit or the control of the circuit mechanism such as lighting or black-out,

may be effected at any time from any point near or far, and irrespective of the distancewherea local or long distance telephone in the syst'e'rnis' accessible or available, inste'atiiof only .atffixed or set intervals unless manually changed or, re-, quiring an attendant, or involving expense there of, such as where, controlled by;clock,or clock actuated switches, and altered bymanual-inter vention where weather conditions changeoralter the times when'it is necessary or desirable to turn, on or off .the lights, as often happens, and which requires personal attentionor manual intervention of an attendant. V

,Another object of the invention is ,toprovide a circuit control system which may housed in conjunction with the usual clocks forcontrolling or operating switches for turning the lights on or off, or permitting the elimination of the clocks and the expendituresincident to ,theiruuse and maintenance, and ,Whichpermits or makes use of a telephone system or circuit,-or vother com municating system already established through,- out, wherebythe lightingmay be turnedonor off at any point from any other point near or remotetherefrom and whichgmay be economically and easily installed simply by removing one of the bells located in the callbox of thesignal circuit of a telephoneset or substationand installing the necessary switch. to actuated thereby in oonjunction, with the controlling circuit, so that the device will be dep'cndableiand in position for-operationat all times. I

Another object of the invention is to provide means for automaticallycausinga blackjgoutjor turning off a sectionof a lightingsystemiisuch as; a city, ,area, building, or home, prior turning the same on, merelyby-calling tw,o diff erenttelep n mb al at s-p ,su sta snone for turning the lights on, and the ;other for turning off the lights, by introducing two switches adjacent the telephone signals or call boxes for mechanical operationgbut without electrical connection or afiecting the communication or signal circuits of the telephone system, v Other objects and advantages will appear and be brought out more fullyin the following sil n ification, v l v Fig. 1 is a diagram oi a, syste1 n ,of electric circuit control in accordance with theinvention and showing a twopolesinglethrow contactor switch and two telephone 'call stations with switches, one of whichis normally open, and

theother of which is normally closed;

the switches closed;

Fig. 3 is; a similar view, but showing all ,of

the switches open;

Fig 2 is a similar view, but showing allot 1 but showing the circuit connected to an oil switch operated by a motor wound spring and clock controlled as well as a solenoid controlled switch; and

Fig. '7 is a View showing three positions of the clock controlled switch.

Referring to, the drawings in detail, I0 and H designate :the line wiressupplying current from a suitable source in the ordinary 110 volt supply circuit, or the like, leading to the conductors l2 and I3 connected to a lighting circuit in which a suitable load, machinery or current consuming devices or units may be connected and illustrated by a motor [4 interposed in the circuit to oper- 'ate.certain equipment, but which motor may be employed to operate an oil or other giant switch controlling a circuit of considerably greater voltage and, loadwhich may control the lighting system of a large building, city, area, or section th reoispringof alarge eleotric oil switch which controlsthe lighting of a boulevard or other area or machinery. Interposedin the supply lines l0 and H leading to the conductors or lines l2 and-l3 may be a suitable switchl5- conventionally illus-,

trated asatwo pole single throw co-ntactor switch having the blades or movable contacts l6 and I! connected as at lilto move in unison and normally openedby gravity, or otherwise withre; spectto the contacts l9 and 20,with which they cooperate to close the circuit. This switch may be operated magnetically or, otherwisef'but is shown connectedas at 2| with a magnetic core operated by an electro-magnet or relay 22 which, upon being energized, will close the switch, and which, upon being de-energized, will release the switch to permit the-same to automatically open by gravity or otherwise,as previously pointed out.

A thermal overload" 23 may be included in the line ,l? ,for the purpose of protectingthe circuit ahdIthemotor or other equipment or current" controlling the lighting 'of a large buil'ding,'boule-f vard or I other .area, city "or section thereof, such 9.51600 to 1000 or 2000 or more volts, a normally openQswitch'zd and a normally closed switch 25 preferably 'of the momentary :contact .type or a snap switch which may be of a type such'as shown in Patent'No. 1,960,020, dated May.22, 1934 are positioned adjacent oiy i'n juxtaposition to thesignal or call boxes 26 of two telephones comprising the usual set, including asignal or call box, receiver andtransmitte'r off the two subscribers lines "or'substatio'ns 21. and 128 of a ftelephone system, which, forcon'vr'i'ience, may

have the numbers Lights2222 maniacs-011153333;

respectively. Each box houses' a' signal or. call mechanism of therespective telephone numbers, whips. as s gr eted. b mass s a This motormay be usedto wind the circuits; including selectrici magnets or? solenoids 29 s. and 305 operatingijanz oscillating. or: pivoted are mature :3 l l having aihammer, striker; :clappe'r or hell "ringer :3'2 zwith a spring. metal-tongue and ball adaptedi'td strike and sound a painofi 198118,?fi9i0f whichi's removed or. omitted 'forQthe purposes of the present: inventioripbut :iwithout' preventing the signahor buzzer-L from: sounding" on thegother; bell. Otherwisec the telephone set; isstheisame as normal'landaundisturbed to operate (inc-the u'suaLinanner fortelephoneconyersations or out-+2 going calls unless. the signal isioperatedatoring the other bell in accordance. "with the-present invention ion anqincoming call',;as;.will bel lhlifir described: The line or-return:;l I 'isgconnectedby a conductor 3.4;;to oneterminalkor binding postot the normally iopenvsw-itchl'gzll andthemthen ter: minal or bindingpost :thereof is: connected ,by, a conductor: 35 t'oone terminal :or binding, post of. the? normally closed switch, 25; The supply or lead 'line 1 ill, is connected around, the switch; 15, by a conductor. 36 m. one end oi the-coil. or' wind: ing ofathe; electro-magnet or vsolenoid ,22 with" an interposedz-mechanical thermal unit or V thermal f cut-out 3'igforming1 a circuit breaker;v which; operates on; an overload in the {circuit by; or from the thermalloyerloadf23gto break thecircuit to the electror-magnet 22 so that the same-willbe deeenergizedpand releasethe ,switch:;l= to ;,nore

mally, open.andprevent:damage Therothen i or opposite endof the coil of ,the'electro-magnet or solenoid ,22 ,is connectedby a conductor 38 to the other terminal of the i normally closed -swltcl 25. ,I11,,addition,'a third conductorv ,39 extends;

from; the terminahofthe switch blade hl 1 to the conductor. 35 ron; completing; a; circuit-through,

eitherone or ,both oftheswitches-ill and under certainconditions; as will be hereinafter; explained. jlttm'ay alsoiebe mentioned thateach;

one of the'switchesg25yand zahasgangupwardly t extending: arm nor. lever '1 4 ll which; is .1 positioned adjacent one;side of, eachzstriker 32;;whereyer the particular numbers-may belocated at -adJacent; or distant points relative toseacheother', but;- they maybe :locatedin :the'same home-.01 build-,

the, switch I5'Yis normally open ;by:;the-qdeenergi -L zation'of ,thegoperating magnetj 2 ,and the switch;

24 open while the switch 2 5 is closedji it is desired to close the. circuit; to thegmotori lfii or :lights therein or controlleduthereby or tootherlmae, chinery, equipment or current,consumingdevices or'units, such as for thepur-poses otgturning on the lights of a building or areabeforegoraftenai black-out, an authorized person-4, lifts; the ,telephone. at his desk, or anyztelephone in: the local or long distance system, and-e" calls, thee-number, Lights 22221atthe particular locality in which the system'is installed, either through. an'opera'tor or automatic dial system.-*-When'- the connection is' made, the magnetsorj' solenoids 29 Land sofathe" particular numberorsignaL device-11 thereof are energized to operate the striker '32 and may signal the bell 3.3, =or"the 1atte"r mayr-bexomitted ntirely.= This movement of itheistriker 32: causes: it :to engage the arnii or lever 40 ofthe-normally 1, open 7 switch'24 and-by aslightmovementmechanically operate'the latter to close the same to complete the closing circuiflth-rohgh the 'electromagnet .122 to energite -the s'ame and .close the switch 15, thus tu'i ning onthe lights thereinor controlled thereby, 'suclt as'by means ofthemotorJ-M which may operate Ta suitable L011 iswitch or the: like: of sufiicient :ca'pacity according to rthelarea' or -sec;

"10 ti'onzbeinglcontrolledj:such as a -city,"section thereof boulevard system, .or .other lightingifuni't, machinery or load. In thisiinstance, the circuit is: traced-Horn; the leacl iii to' the conductor 38 through the thermal unit 31, magnet 22, conductor .38 through the normally closed switch 25, conductor through the: momentarily closed switch Z'diwhich;fas 'before stated, :hascbeen closed by the striker 32 .engag'lng :the arm or lever .40,*and then throughrthe: conductor 34.1110 thev line wire I I; The switch, 2,4:will;however;immediately re:- turn toara; ln'ormally open position to, break the closing circuit, but the: switch: I 5 will be retained in axclosed'. position by thegholding circuitwhich iscompletedby the closing of theswitch 25:; ,This holding circuit-is traced. from the lead I Uthrough the conductor and thermal unit 31 tothemagneta22 and then through the. conductor-381 and switch: 25 tomithe conductor 35 with sthe return through the-conductor 39 and line I i through the switch :blade I 11* which has -been momentarily closed through therclosing of,-t h'e:switch124,andwill remain-closed with the switch 15- so that the lightsor power will remainiin theicircuit directly controlled ,by-the" switch I 5 foryas long;as desired, Ordinarily, this circuit is :controlled byaa clock controlled switch L which may ibe, omitted or used: in ;conjunctio n with the present system, if E,.-de-,. sired. j-"The iusual diflicultyqwith, such clock cone trolledgswitches is; that, weather conditions yary, and if, [set for certain times toclose and open'a lighting circuit, darkness may come .onfrom a storm, and there will beino lights or, the light- I of-,,=the;day;may come onlgefore or laterthan the time-set, orjdarkness may come QnearIier-or be delayed, so that operation of the switch, ,or ,cire cuitcontrolling the lights will haveitobe' affected manually in orderto meetthe particular circumstances, andthe cost ,of,;installation.,and maintenance thereoi is considerable, if not excessive;

elephones for operating the present circuit, wh main-lyintendedqto be called in the usual way, may be automatically actuatedin any suita le m h hat: stated n erv s. r certain times bu t i e abl eop ra t e same aS, de-' scr ed to; suit particular conditions suchias conditw s 'Qiw athera rl a u rl iorthe urpose ing. in-th li hts or a insa l c t U gcostof installation andmaintenanceis prac cally-nil, or very low. ;;;Forthe purp0se of a better understanding-citric switches fil and 25, ima e b a nedlth these sw ch s. a e

made in both normally open and normally closed form, iand the ones diagrammatically illustrated: each consist ofa contact arm operatively mountediso that its" freeend moves between two stops or contacts and the arm usually comprises athin leaf spring: of Every thin beryllium; Phosphor bronzelffa fcopper strip or' ribbon, 'or other metal operatively supported at oneiiend in'cantilever fashion, the other'end being; free to move The strips -or stops are preferablyof silver or other metal tosminirnize damage resulting fromfarcing durin'githe making and breaking of an electrical 1 type -with butv slight movement: of ii the arms or leversiflllrrequired tdclose onopem thebsame, and; 01 courseiv thiSl-iS momentary.by theooperatiomot, astriker: 32; of the -,si'gna1-,\ afterwhichethe switch will. I return totits normalzposition; in which the" switch .24 is open and the-switch 2-5iis closed;

As before. stated, the;- circuit including the switch I5 when operated. to turn on the;. l-ightsj and close the; circuit. through: the. switch-2 4: from the-positionshown-.imFig L of the drawings; will: cause the completion; .ofsthe .circniin as, shown-in Fig.- 2 of Ethel drawings. whemtheeholding circuit is.- efiective. Therefore; when it? is; desirede to again open the. circuit, such as for: turning :off the lights I iduring av black-out; such-l authorized person merely'acalls the otheritelephone.Immber,

open as long as desired to extinguish the lights 1 orbreak the I circuit t0- th'el-motor I 4- or lights controlled thereby, 01 170 other current consuming devices. The closing of the circuit maybe completed merely by again. calling Lights. 2222,- as' previously described; and-while the telephone system is used :to control :theoperation thereof,- no currentis -taken from the telephone lineinor any electrical connection mad'etherewith; asthe operation of the s'witches 24 and 254's purely mee chanical from the strikers-32; while the telephone system operates the I usual way, and-al1 that is necessary is to-mount-the switches -24 and 25 m proper relation to the telephone signalpboxes 2 1 and- 28 in the circuitcontrol-ling the operation tion'. thereof 'is' not repeatedat this time;

mama

electrdemagnetdl: The contacts 141*: and" l8.=:are

c'onn"ected-tothespivot.terminal;=5itioi tlrie switch bladei52l-andtthe contact/5A, respectively, and

open the sameatfimal m bytway -of example and therefore, will: not operate at other times, this beingtaken careohbycalling the-telephonenumbers for-turning the lights on -or off in-the-.manner previously described in connectionwith Figs 1 2 and-3'=ofl thetdrawings} and therefore the opera.-

The three -way mechanicallyoperated switch 56 is mechanically; reversed when the oil switch is oper-' ated by-themotor I4, thetmotor serving towind a spring which; upon-reaching a.-centaim-tension-,

is automati'callyweleased I to reverse the position of the switch blad'e 58, asis common-in thistype of switcht In Fig. '7', the switches 5 I' and 56's are shownclosedtdcomplete the circuitto'the motor inthe-letthand position-when the lights goonat -30 6-p.- mi, while the intermediate position shows the switchisopen afterthe lights have. been turned onafter' 6:12; mi, theswitch blades having beenadvanced l80-"degrees aftereach movement to contacting -position= and in the-thircl or right hand-1 position; the -position of the switchesis of the switch l5, and thismay :bethe present clock operated: circuit-in -which the present systern is installedin conjunction with---the clocks, but preferably totake the-place-thereof with-the additional advantages referred to above, includ ingthe important fact thatthe circuit may-v-be operated to extinguish or turmonthe lights at anytime for-a Jolackoutoraccording'to variable weather conditionsand meet all possible e xi'g'er1 cies whichmay occun'as well' as being 'capable of operation locally or at any; distancewwherever --'atelephone i'saccessible. I

In Fig.6 of the drawings, the'conductors I 2 and I3 -are extendedto an electro magnet oprelay- 42,- the core 43 of whichoperatesanormallyopenshownopen-at -6 a5 me, when the lights are turned off In Fig. fisthej ccn ductorsl land I3 are shown extended ior-connection with asolenoid-or e180:- tro-magnet 'fifi -where onlya solenoid controlled switch is used In each-instance, it is understood that themovable contacts-0t the solenoid-operated switches are moved into one position when I the-electro-magnets are energized and-automatthree-way contact switch 5I- has a blade '5'2-tpiv-- oted at 53" and cooperating-withcontactsand withanintermediate-neutral --position.- A three-way mechanicallyreversed swi-tchifi -is con-- nectedsin circuit for operation-bythe motor a I 4;

one terminal athereof -leading to the' pi'vot :point 5'! Loire. movable contact blad .58 which: cooperates with spaced contacts Hands, a'n-sdifierent positions 0f ;thQ.SW-it(3h:b18 de.,' while the intermedi ate; position is; neutrals The contacts 54 (and; :59."

are connected-thy J a conducton SI and; th cone tacts I55 :and arev connected byraiconductorufil with? the contacts; 49 and; 50 interposed and for-me irgsa gap therebetween,adapted,tmbelclosed; by

movable; qntact-fliroperatedxlm the relay-pr.

' that it-takes--care of.all=possible cidnditions with i'cally move to -another or open: position when the electro-magnets arede-energized, and this movement in r all of -;the switches is made-- quickly .to v avoidk arcingo Thelmovable contact -6'I ofthe solenoid controlled switch having-the 'electro-magnet orsolenoid -66 i cooperates with contacts 1 68' and=69 controllingthe.circuit,-.- including conduc tors 'IIl and -H, so that when; thecircuit 'isclosed at --the .electro.-magnet. 66, the I armature or core thereof will be attracted to-closethe circuit-across the contacts 68 and 68., In view of the foregoing, it is thought that theoperation of the device"will be readily"understoodganddt' will: be seen high or low voltage; since the-conductors and 64,. instead-of bein g connected -to -the line wires Ill-and II may be connected to a'ny-supply circuitof any de'sired voltage,.accordingito-the purpose forwhichtheoperating Mcircuit ;is.=,used, and at the .amperage required, but operated with:-the clock switches stationary.- I

It will: thus -beseen-that lights or -othere'lectrical equipment vmayh-be turned. on;- .or H off-eat any time .i'desired, notwithstanding thecondition of the operating -:circuit or the setting of--the clocks operatinsnr controlling the .oil; switches for. turn.- ingothe'lights omoreofie our-controlling the'lights or. othen electrical, w apparatus or equipment,-

that'-.the',-lights Lori suchilapparatus or. equipment. may ,-be. turned ofi at any time ;desired irrespectite'oftheposition of=the clocks Thus,-the lights may \be-iturned-tofliearlieninithw mornings-onion later in the evenings if day light comes on earlier or persists later. Thus, saving "considerable in the cost of lighting and correspondingly in the operation oflother electrical apparatus or equipment.

While I have illustrated and describedthe preferred form of construction for carrying" my invention into eilect,this is capable of variation and. modification without -departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself ofsuch variation and modifications as come within the'scope of the appended claims." i

Havingthus described my invention, what I claim as new'and desire to secure by Letters Patentis: I

1. In a system tion with 'a power circuit having current con-v suming units and a switch. for controlling-said circuit, of a communication circuit electrically independent of said power circuitand having a pair of signal means for each call station each with a different call number, and-meansniechan ically actuated by one of said signalniean's for causing actuation of said power circuit switch to close said circuit,'and means mechanically ac-' tuated by the other signal means for causing actuation of the switch to open the circuit. r

2. An electrical circuit-controlsystem comprising the Combination with an electric communication circuit havinga call means and a movable element operable upon actuation of the call means, of an operating circuit normallyopen', means for closing said latter circuit, and means in another circuit mechanically operated only by said movable element upon actuation of the call means to affect the operation of said closing means for the operating circuit. 7

3. An electrical circuit control system com: prising the combination with an electric'telephone circuit having a, call device with a movable element, of an operating circuit normally open, means for closing said-circuit, another circuit for electrically operating said closing means and means in the latter circuitoperated mechanically by the movable element upon operating the call device to open or close said circuit last named said telephone circuit being electrically independent of the other circuits.

4. The combination with a telephone communication circuit, of a power circuit unconnected to the telephone circuit and having normally open control means, said telephone communication circuit having asignal means identified by certain call indicia with a movable element and another circuit. independent of the telephone circuit for operating said control means to open or close the same and the circuit controlled thereby, including a switch operated by said movable element upon operating said signal means.

5. A communication circuit having a pair of associated call means each having a movable signal element identified by different call indicia, in combination with a power circuit electrically unconnected to the communication circuit, a circuit closer in said power circuit, a circuit electrically connected to said power circuit and including means to open said circuit closer when one of said call means is actuated and to close said circuit closer when the other of said call means is actuated. l

6. The combination with a communication circuit having. stations, of a power circuit having of electric control, the combina control means, said stations of the communication circuit having each a signal means with a movableelement and another circuit for operating said 'control means to open or close'the same and the circuit controlled thereby, said third circuit-including a switch positioned to be physically operated by said movable element upon operating the signal means of difierent stations without electrical intervention or connection with said communication circuit.

7. An electrical circuit control system comprising thecombination with an operating circuit for controlling lights or other equipment and having a normally open switch means electrically operated for controlling the same, of a telephone circuit having call stations each with the usual signal device including a striker, a circuit for operatingsaid control device including actuating means'therefor, and switches positioned to be operated by said strikersupon, movement of the latter to momentarilyefiect said jcontrolling circuit to close said normally open switch means and to release the same to close" and open the operating circuitrespectively.

8.' Ina system of electric circuit control, the combination with a, power circuit and a normally open switch in said circuit; of an operating circuit having means for closing said switch, a pair of signal devices included in a telephone circuit, a normally open switch in said operating circuit adjacentthe signal operator of one device and ajnormally closed switch in the telephone circuit ad'jacent the signal operator of the other signal device, to momentarily close or open the circuit through said switch closing means.

9;'In a system of electric circuit control, the

combination with a power circuit and a normal- :l-y' open'switch in said circuit; of an operating circuit having means for closing said switch, a pair of signal devices included ina telephone circuit,- a normally open switch in said operating circuit adjacent the signal device operator to be closed upon actuation of the signal device operator adjacent thereto and a normally closed switch in the operating circuit adjacent the signal device operator of the other signal device to be opened upon the actuation of the signal device operator adjacent thereto for closing and opening said power circuit respectively, said latter switches being free of electrical connection with the telephone circuit.

10. The combination with a power circuit such as a lighting circuit, having electrical means of opening and closing the same, of a control circuit including said means, and having separate normally open and normally closed switches for closing and opening said control circuit, and adapted to be mechanically operated by the signal devices of two telephones of a telephone system for closing and opening the circuit to the electrical means of the power circuit for closing and opening the latter respectively.

11. The combination with a power circuit such as a lighting circuit, having electrical meansof opening and closing the same, of a control circuit including said means, and having separate normally open and normally closed switches respectively for closing and opening said control circuit, and adapted to be solely mechanically operated bythe signal devices of two telephones and aholding circuit includin said eans, closed by closing said control circuit at one of said switches through the other of said switches and opened by opening the last named switch.

' 12. The combination with the electrical circuit, of a communication system having signal devices with a movable part for each call station; of a power circuit, a normally open switch in and controlling the power circuit, a control circuit including electrical means for closing said switch, a holding circuit also including said closing means to hold said control circuit closed, and movable means adjacent a signal device operated wholly physically by a movable part to close thecontrol circuit upon operation of the signal device to close the holding circuit and movable. means adjacent another signal device operated wholly physically by another movable part to open the control and holding circuits to permit the first switch to open.

13. The combination with the electrical circuit,

of a communication system having signal devices for each call station; of a power circuit, a normally open switch in the power circuit, a control circuit including electrical means for closing said switch, a holding circuit also including said closingmeans, a normally open momentary contact switch positioned adjacent one signal device for purely mechanical operation thereby to momentarily close the control circuit to close the first switch and holding circuit to maintain the last named switch closed upon calling the phone having said signal device, and a normally closed momentary contact switch positioned adjacent another signal device for similar purely mechanical operation thereby to momentarilyopen the control circuit at such point and also open the holding circuit to release the closing means of the first switch and permit the latter switch to open the power circuit.

14. The combination with a telephone circuit and signal devices of substations therein having strikers, an operating circuit including a normally open switch,a working circuit having clock operated, switches and a control circuit includ-" ing an electro-magnetic device for closing said open switch, a holding circuit therefor,:and a pair of contact switches, one normallyopen and the other normally closed and connected to. each other so that the holding circuit is completed by closing the open contact switch while the other is closed, said pair of switches each having an oper ating arm in juxtaposition to the striker of a signal device for operation thereby.

15. In a system of electrical circuit control, a power circuit constituting an operating circuit, a normally open switch in said circuit for controlling the same, a communication circuit having at least two independent calling stations each with a call device having a movable element, a normally closed switch having an actuating part adjacent the movable element of one call device, a normally open switch having an actuating part adjacent the movable element of the other call device for opening and closing the switch controlling the power circuit free of electrical connections with the communication circuit, a holding circuit established by the closing of the circuit to the control switch and opened by the opening of the second normally open switch to open and close said power circuit.

16. The combination with a telephone circuit and signal devices of substations therein having strikers, an operating circuit including a'normally open switch, a working circuit having time controlled switches and a control circuit including an electro-magnetic device for closingsaid open switch, a holding circuit therefor, and a pair of contact switches, one normally open and the other normally'closed and connected to eachclosed but normally open contact switch to permit the same to open.

PETER HINSHELWOOD. 

